Meaning of napkin math | Babel Free

Definitions

The act of performing quick mathematics often as a means of estimation, as if done on the back of a napkin (or in one's head).

Canada, US, uncountable

Examples

“Based on my napkin math—and keep in mind I am terrible at math—if you made every conscious choice to do right, your highest potential “life grade” is a D once your bad habits are subtracted.”

CEFR level